Supporting profiled element, method for producing a supporting profiled element, and use of said supporting profiled element in a method for producing a reinforced vehicle fuselage component

ABSTRACT

A supporting profiled demerit is configured to support a reinforcing profiled element that is formed from a fiber composite semi-finished product during a curing process of a method for producing a vehicle fuselage component, during which the reinforcing profiled element is bonded to a surface of a fuselage shell that is also formed from a fiber composite semi-finished product. The supporting profiled element includes an air-impermeable profiled hose having two ends and a first end piece that is detachably inserted at a first of the two ends of the profiled hose so as to form an insertion connection. The first end piece is sealed against the profiled hose by the insertion connection.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase application under 35 U.S.C.§371 of International Application No. PCT/DE2011/001346, filed on Jun.16, 2011, and claims benefit to German Patent Application No. DE 10 2010024 120.2, filed on Jun. 17, 2010. The International Application waspublished in German on Jan. 26, 2012, as WO 2012/010134 A1 under PCTArticle 21 (2).

FIELD

The present invention relates to a supporting profiled element, a methodfor producing a supporting profiled element, and a method for producinga reinforced vehicle fuselage component.

BACKGROUND

A supporting profiled element of the type in question is known forexample from DE 101 56 123 B4. This supporting profiled element is usedto support a reinforcing profiled element, which is formed from a fibrecomposite semi-finished product, in a curing process of a method forproducing a cover element (for example for an aeroplane) which isreinforced by the reinforcing profiled element. In this curing process,the reinforcing profiled element is bonded (what is known as“co-bonding” or “co-curing”) to a surface of the cover element, which isalso formed from a fibre composite semi-finished product.

In general, there is a need for a supporting profiled element of thistype whenever there is the risk of the reinforcing profiled elementdeforming during the curing process as a result of the shaping of thereinforcing profiled element which is to be bonded. In this context, itshould be noted that in fibre composite methods of this type, the“substrate” (for example the fuselage shell of a vehicle fuselagecomponent) is generally introduced, together with the reinforcingprofiled element which is bonded thereto, into a casing, which issubjected to pressure from the outside.

The reinforcing profiled element can be prevented from deforming in thismanner by the supporting profiled element, which extends parallel to thereinforcing profiled element and contacts it at least in portions.

With a view to the advantage expected from fibre composite technology ofa high specific strength of the fibre composite component which is to beproduced, a supporting profiled element which is used during productionshould be removed again once the fibre composite semi-finished producthas been cured and connected. In the production of the fibre compositecomponent as disclosed in DE 101 56 123 B4, the supporting profiledelement which is used in this context can be drawn out, for examplelaterally, from an intermediate space of the approximately C-shapedreinforcing profiled element once the fibre composite semi-finishedproduct has been cured. The supporting profiled element could forexample be manufactured from metal (for example aluminium), for exampleas a milled metal part.

By contrast, however, shapings and arrangements of reinforcing profiledelements which do not make it possible to remove the supporting profiledelement sideways (transverse to the longitudinal direction of thereinforcing profiled element) after curing, because it is “caught”between the substrate and the reinforcing profiled element in thisdirection, are also conceivable in a curing process of this type.

In particular in a case of this type, it may be provided that thesupporting profiled element is drawn out in the longitudinal directionof the reinforcing profiled element, rather than the transversedirection, after the substrate and the reinforcing profiled element havebeen cured. However, in many cases this requires that the supportingprofiled element is manufactured from a flexible material, rather than arigid material such as aluminium, so as to ensure sufficient flexibilityof the supporting profiled element for it to be drawn out. A flexiblesupporting profiled element is therefore often required, in particularin the production of vehicle fuselage components which are curved in acomplicated manner (for example cover panels of aircraft, etc.).

“Rubbercraft Corporation of California”, USA, supplies such flexiblesupporting profiled elements manufactured from an elastomeric materialor single-piece bladders up to 14.6 m in length (“single piece bladdersup to 48′ in length”) for use in the production of compositeconstructions and composite components (websitewww.rubbercraft.com/tooling.htm as of 10 May 2010). When supportingprofiled elements of this type are used, which are manufactured so as tobe tailored for a very specific application, they are affected to somedegree, in such a way that they can generally be used at most a fewtimes for component production of the type in question. This results inhigh costs for providing the required number of supporting profiledelements, in particular in the mass production of vehicle fuselagecomponents, which are each provided with one or more reinforcingprofiled elements.

SUMMARY

In an embodiment, the present invention provides a supporting profiledelement configured to support a reinforcing profiled element that isformed from a fiber composite semi-finished product during a curingprocess of a method for producing a vehicle fuselage component, duringwhich the reinforcing profiled element is bonded to a surface of afuselage shell that is also formed from a fiber composite semi-finishedproduct. The supporting profiled element includes an air-impermeableprofiled hose having two ends and a first end piece that is detachablyinserted at a first of the two ends of the profiled hose so as to forman insertion connection. The first end piece is sealed against theprofiled hose by the insertion connection.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described in even greater detail belowbased on the exemplary figures. The invention is not limited to theexemplary embodiments. All features described and/or illustrated hereincan be used alone or combined in different combinations in embodimentsof the invention. The features and advantages of various embodiments ofthe present invention will become apparent by reading the followingdetailed description with reference to the attached drawings whichillustrate the following:

FIG. 1 is a schematic side view of an arrangement for producing areinforced vehicle fuselage component,

FIG. 2 shows a part of the arrangement of FIG. 1 from above,

FIG. 3 is a detail from FIG. 2,

FIGS. 4 to 6 are various perspective views of an end piece according toa first variant which can be used in a production method according toFIGS. 1 to 3, and

FIGS. 7 to 9 are various perspective views of an end piece according toa second variant which can be used in a production method according toFIG. 1 to 3.

DETAILED DESCRIPTION

An aspect of the present invention is to provide a supporting profiledelement of the aforementioned type, which can be provided in a simpleand cost-effective manner and which can advantageously be used, inparticular, in the production of a reinforced vehicle fuselage componentusing fibre composite technology.

The supporting profiled element according to the invention comprises anair-impermeable profiled hose and at least one end piece, which isdetachably inserted at one of the two ends of the profiled hose and issealed against the profiled hose by means of this insertion connection.If an end piece of this type is only provided at one end of the profiledhose, the other end of the profiled hose can for example be closed, andthus sealed, by welding or gluing the profiled hose material.

However, in a particularly preferred embodiment, the supporting profiledelement according to the invention comprises detachably inserted endpieces, which are sealed against the profiled hose by means of thisinsertion connection, at both ends of the profiled hose.

By using a profiled hose, sufficient flexibility of the supportingprofiled element for the respective application can be achieved,depending on the shaping (for example wall thickness) and type of theprofiled hose material. Preferably, the profiled hose is manufactured,for example extruded, from polymer material (for example silicone). Oneor more materials can be processed (for example in a co-extrusionprocess) so as to produce the hose. In particular, the surface of thehose for example may be specially treated so as to form a “functionallayer” (anti-adhesion layer) and/or may be formed from a specialmaterial, which is different from the material beneath it. In this way,it can be made easier to slide the hose out from the cured matrixmaterial subsequently when the supporting profiled element is removedafter the curing process is complete. The surface may for example beformed by a fluoropolymer layer. It is also possible to turn to measureswhich are known per se for mechanically reinforcing the hose, forexample in that one or more reinforcing layers (for example fibrenettings, etc.) or other reinforcing elements are introduced into aflexible hose material.

By contrast, the end piece or pieces which are detachably inserted (atone or both ends of the profiled hose) may be manufactured from a morerigid material, preferably for example from a metal material such asaluminium. As a result of the sealing, provided by means of thisinsertion connection, between the profiled hose and the end piece(s), aparticular pressure can advantageously be maintained or set in the hoseinterior during the curing process, and this ensures or increases thedimensional stability of the supporting profiled element.

As will be explained in greater detail below in the description ofembodiments, the sealing provided by means of the insertion connectionitself need not be “perfect”, in the sense that this sealing willsubstantially resist an (air) pressure difference between the hoseinterior and the hose exterior which occurs during the subsequent curingprocess. Rather, it is sufficient for this degree of sealing effect onlyto be achieved in the curing process itself, in that during said processthe ends of the profiled hose are pressed sufficiently strongly againstthe portions of the end pieces which they enclose.

The materials which are used for the profiled hose and the end piece orpieces should be selected in such a way that they resist the conditionswhich are to be expected in the curing process. For example, in currentcuring processes for fibre composite components based on epoxy resin,maximum temperatures which are typically in the range of approximately150 to 250° C. are achieved.

The detachable insertion connection according to the invention betweenthe end(s) of the profiled hose and the end piece(s) has the advantage,which is particularly consequential in practice, that at least each endpiece (with corresponding shaping) can be reused, and that with an endpiece of this type, which can be used repeatedly if desired, asupporting profiled element which can be reused for a further componentmanufacturing process can be provided in a simple and cost-effectivemanner, specifically by simple insertion into an end of the profiledhose (for example of a new profiled hose). Especially if an end piece isprovided at each of the two ends of the profiled hose, it is of greatadvantage to be able to use the same end pieces for providing supportingprofiled elements of various lengths (the length of the supportingprofiled element is determined by the length of the profiled hose usedfor forming the supporting profiled element).

The cross-section (profile) of the supporting profiled element should beselected in a manner adapted to the relevant application. Thiscross-section may in particular be composed of cross-section portionswhich extend in straight lines, for example in a trapezium shape or in arectangle, but also for example with one or more cross-section portionswhich extend in a curve.

For supporting a reinforcing profiled element in the form of what isknown as an omega profile, a trapezium-shaped supporting profiledelement may for example advantageously be used. For supporting a Creinforcing profiled element, a rectangular supporting profiled elementfor example is suitable. For supporting a double-T reinforcing profiledelement, rectangular supporting profiled elements arranged on both sidesthereof may for example be used.

If the fibre composite component having a plurality of different typesof reinforcing profiled elements, which is to be produced using fibrecomposite technology, is to be provided on a (planar) substrate,different supporting profiled elements, which are each adapted to theshaping and arrangement of the reinforcing profiled elements, may alsoaccordingly be used.

What is known as a “pressure shadow” can also advantageously beprevented with the supporting profiled elements according to theinvention.

The supporting profiled element according to the invention can be usedin particular for supporting a reinforcing profiled element, which isformed from a fibre composite semi-finished product, in a curing processof a method for producing a vehicle fuselage component (in particular anaircraft fuselage component) in which the (at least one) reinforcingprofiled element is bonded to a surface of a fuselage shell which isformed from a further fibre composite semi-finished product (what isknown as “co-bonding” or “co-curing”).

This is of relevance in particular for manufacturing, for examplemass-producing, fuselage components in which the fuselage shell has asurface area of several square meters and/or an extent of a plurality ofmeters in at least one direction.

The term “fibre composite semi-finished product” used herein denotes amaterial comprising fibres which are embedded in a (cured) matrixmaterial, at the latest after the curing process is complete, andreinforce this matrix material and thus form a “fibre compositecomponent” together with the matrix material. The fibre compositesemi-finished product may for example comprise a woven fabric, interlaidscrims, a fibre mat or the like, or contain a textile of this type.

In particular a thermosetting plastics material, such as epoxy resin,may be provided as the matrix material. Each fibre compositesemi-finished product which is used in the invention may be provided forexample as a “dry” fibre material. Alternatively, the fibre compositesemi-finished product may also already be “pre-impregnated” (for examplewhat is known as “prepreg”) with the matrix material (for example asynthetic resin system).

Accordingly, in the method explained above for producing a vehiclefuselage component, the fuselage shell and/or the reinforcing profiledelement are already in the form of a pre-impregnated fibre compositesemi-finished product before the curing process. A prepreg of this typemay for example be cured thermally (at an elevated temperature).

However, if the fuselage shell or the reinforcing profiled element isinitially in the form of a “dry” fibre composite semi-finished product,this still has to be infiltrated with the relevant matrix materialbefore the actual curing. This infiltration can be carried out forexample in the same tool or the same arrangement in which the actualcuring is (subsequently) carried out.

The term “curing process” used herein is accordingly intended also tocomprise a process in which the actual curing in the stricter sense ispreceded by an infiltration step, in which in particularnon-pre-impregnated reinforcing profiled elements and/or anon-pre-impregnated fuselage shell are further infiltrated with thematrix material (for example epoxy resin system).

In principle, the supporting profiled element according to the inventioncan be used for the production of fibre composite components containingany desired fibre materials and matrix materials, in particular oneswhich are known per se.

Possible fibres include glass fibres, carbon fibres, synthetic plasticsmaterial fibres, steel fibres and natural fibres.

In particular plastics materials such as thermosetting plasticsmaterials (synthetic resins) are beneficial as a matrix material. In aspecial embodiment, the supporting profiled element is used forproducing a carbon-fibre-reinforced plastics material component (CFRPcomponent) in particular comprising a matrix based on epoxy resin.

In a preferred embodiment of the supporting profiled element accordingto the invention, an outer portion which projects from the end of theprofiled hose extends at least one of the end pieces of the hose profilein a flush manner. This has advantages in particular in connection withthe use of an air-impermeable film, which is laid over the reinforcingprofiled element(s) during the curing process.

In this connection, it is also advantageous for an outer portion of anend piece, which projects out of the end of the profiled hose, to haveinclined faces for laying an air-impermeable film of this type which isused in the curing process.

In one embodiment, it is provided that an outer portion of the or atleast one of the end pieces, which projects out of the end of theprofiled hose, is provided with an air passage opening for applying apredetermined pressure to the hose interior during the curing process.

This opening preferably comprises a threaded hole for screwing in anappropriate sleeve-like air passage screw, which makes it possible toapply pressure to the hose interior through an opening (hole) of anair-impermeable film, which lies against the outer portion in a planarmanner. In this context, the air passage screw can be used for fixingthe film in a sealed manner (between a screw head and the aforementionedouter portion).

In a preferred embodiment, it is provided that an inner portion of anend piece, which projects into the end of the profiled hose, is providedwith at least one sealing ring for sealing to the attached end of theprofiled hose. A sealing ring of this type may for example be formedfrom an elastomeric material. In a preferred embodiment, the sealingring is manufactured from a silicone material.

In a preferred development, the sealing ring is laid in acircumferential groove which is formed on the end piece.

To improve the sealing effect, it may also be provided that a pluralityof sealing rings are provided on the end piece, for example each laid inone of a plurality of grooves, which are arranged mutually spaced asseen in the longitudinal direction of the end piece.

In the simplest case, the sealing ring is of a circular cross-section.However, in a development, an elongate sealing ring cross-section isprovided, preferably in such a way that the extent of the sealing ringis substantially greater in the longitudinal direction than transversethereto (for example by a factor of 2 or more).

With a sealing ring which is accommodated in a groove, it is preferredfor approximately 10 to 40% of the height of the sealing ring to projectout of the groove.

In one embodiment, it is provided that an inner portion of the or atleast one of the end pieces, which projects into the end of the profiledhose, is profiled as seen in the longitudinal direction.

Aside from profiling for providing the aforementioned grooves, in thiscontext, alternatively or in addition, in particular a single ormultiple gradation of the inner portion may be provided in thelongitudinal direction, in such a way that the cross-section or theprofile of the inner portion tapers in such a way that it is simpler toattach the profiled hose.

As an alternative or in addition to the aforementioned sealing rings, atleast one projection which extends around in the circumferentialdirection may also be formed from the material of the end piece itself.A sealing effect can also be provided in this manner. If the end pieceis manufactured from a relatively rigid material, for example as amilled metal part, the projection which extends around in thecircumferential generally does not provide a good (air) sealing effectagainst the profiled hose, but advantageously provides a mechanicalfixing effect. Fixing of this type can for example prevent the end piecefrom slipping out of the end of the profiled hose during handling(manual or automated) with the supporting profiled element.

In an advantageous embodiment, the aforementioned inner portion of theend piece has a first region, as seen in the longitudinal direction, ofa relatively large cross-section and a second region, located furtherinto the hose interior (when the profiled hose is attached), of acomparatively smaller cross-section. These regions can be connected by agradation and/or chamfering. In this context, the first regionpreferably comprises one or more sealing rings of the aforementionedtype, and the second region preferably comprises at least one projectionwhich extends around in the circumferential direction of theaforementioned type.

The method according to the invention for producing a supportingprofiled element for supporting a reinforcing profiled element, which isformed from a fibre composite semi-finished product, in a curing processof a method for producing a vehicle fuselage component, in which thereinforcing profiled element is bonded to a surface of a fuselage shell,which is formed from a fibre composite semi-finished product, ischaracterised by the steps of:

-   -   a) providing a profiled hose, for example by cutting off a        portion of a particular length from a virtually continuous        supply of an air-impermeable profiled hose, and    -   b) detachably inserting end pieces at the two ends of the        provided profiled hose, so as to seal the end pieces to the        profiled hose by means of this insertion connection.

If in step a) the profiled hose is provided with an end of the profiledhose which is already sealed at one end, for example by gluing orwelding, it is sufficient, as an alternative to step b) as disclosedabove, to insert an end piece detachably at the other of the two ends ofthe provided profiled hose, so as also to provide sealing at this otherend (by means of the insertion connection).

The embodiments and details explained above as regards the shaping ofthe profiled hose and the shaping of the end pieces can also be usedanalogously, individually or in combination, so as to develop the methodaccording to the invention for producing a supporting profiled element.These developments are accordingly characterised in that acorrespondingly configured profiled hose or one or two correspondinglyconfigured end pieces are used in method step a) or in method step b).

A further aspect of the present invention provides a method forproducing a reinforced vehicle fuselage component from a fuselage shell,which is formed from a fibre composite semi-finished product, and (atleast) one reinforcing profiled element, which is formed from a fibrecomposite semi-finished product and which is bonded to a surface of thefuselage shell in a curing process of the production method.

According to the invention, (at least) one supporting profiled elementof the type disclosed above is used for supporting the (at least one)reinforcing profiled element during this component production process.The component production may for example comprise the following steps:

1. laying the fuselage shell (as a fibre composite semi-finishedproduct, for example as a prepreg) on a mould face (tool), and preparingthe required reinforcing profiled element or elements (as a fibrecomposite semi-finished product, for example already infiltrated andcured), for example by laying a “bonding film” on reinforcing profiledelement foot portions which are provided for bonding to the fuselageshell.2. laying the required supporting profiled element or elements in therelevant profile recess of the reinforcing profiled element or elements,and laying the combination or combinations of reinforcing profiledelement and supporting profiled element which are thus produced in thedesired position and orientation on the fuselage shell. Alternatively:initially laying the supporting profiled element or elements on thefuselage shell, and only subsequently laying the reinforcing profiledelement or elements.3. producing a space which encloses the fuselage shells along with thereinforcing profiled element(s) and supporting profiled element(s) andprovides air-tight sealing from the surroundings, for example by layinga vacuum film, evacuating this space, and preferably carrying out atightness test. If an autoclave is used, the evacuation and tightnesstest are preferably provided only after the arrangement is brought intothe autoclave.4. optionally infiltrating the fuselage shell and/or the reinforcingprofiled element or elements (if/as much as necessary) with liquid orviscous matrix material, and heating so as to produce the connection(and curing) of the parts.5. once the curing process is complete: removing the supporting profiledelement or elements from the components which is manufactured by“co-bonding” or “co-curing”.

In particular when the supporting profiled element or elements which areused for this fibre composite component production are created inadvance with a new (not reused) profiled hose, a complex advance testfor tightness and any surface damage to the supporting profiled elementor elements, before they are laid on the fuselage shell, is generallysuperfluous in practice. Rather, a tightness test immediately before theactual curing process (heating) is generally sufficient.

By contrast with the procedure outlined above, in a first step thereinforcing profiled element or elements could initially be laid on amould face (tool) with the supporting profiled element or elements, andthe fuselage shell could only be laid subsequently.

In the “curing process”, both the fuselage shell and the (at least one)reinforcing profiled element can be cured. However, this is notcompulsory. For example, one of the parts “fuselage shell” and“reinforcing profiled element(s)” may already be cured in part or evenfully before the curing process in question is carried out. What isimportant for the bonding, which in this case is in the form of“co-bonding” or “co-curing”, of the reinforcing profiled element orelements on the fuselage shell is that there is still liquid or viscousmatrix material at the interface between these two parts at the start ofthe curing process. In one embodiment for example it is provided that,during the curing process, one or more reinforcing profiled elementswhich are already fully cured are bonded to the fuselage shell (inparticular in the form of a prepreg for example), which is not cured oronly cured in part. As an alternative or in addition to a part which isnot cured, or in any case not fully cured, it is ultimately alsopossible to provide a matrix material part (“adhesive film”, for exampleof epoxy resin) which is inserted between the parts.

In one embodiment of the production method, the reinforcing profiledelement is bonded to the fuselage shell while evacuating a space whichencloses the fuselage shell and the reinforcing profiled element, issealed against the environment, and can be delimited in particular by anair-impermeable film at least on the side of the fuselage shell facingthe reinforcing profiled element.

A curing process of this type, which is assisted by negative pressure orvacuum, is known per se in fibre composite technology. However,according to the invention, the manner in which the reinforcing profiledelement is supported (optionally a plurality of reinforcing profiledelements) is configured in a particularly advantageous manner (using atleast one supporting profiled element according to the invention).

In the context of the invention, it is advantageously possible to turnto all developments which are known per se of the curing process itself(optionally combined with a preceding matrix material infiltration).Purely by way of example, it should be noted that the supportingprofiled element according to the invention can also be used in thedeveloped vacuum-assisted infiltration and curing process which isdisclosed in the aforementioned DE 101 56 56 213 B4. Further examples ofmethods which are known per se and are suitable for the use of thepresent invention include for example resin transfer moulding (RTM),vacuum infusion (for example VAP, VARI, etc.) and developments thereof(for example SLI, LRI, BP-RTM), etc.

In a preferred development of the production method, the curing processis carried out in an autoclave. The aforementioned embodiment of thesupporting profiled element—in which, if both ends are equipped with endpieces, at least one of these end pieces is provided with an air passageopening for applying a predetermined pressure to the hose interior—isbeneficial in this case in particular. A particularly simple methodvariant occurs if this predetermined pressure corresponds to thepressure prevailing in the autoclave, and this can be provided forexample by using the aforementioned sleeve-like air passage screw, whichis screwed into a threaded hole in the relevant end piece and projectsinto the pressurised space of the autoclave.

FIG. 1 shows an arrangement for producing a vehicle fuselage component(for example an aircraft fuselage component) form a fuselage shell 10,which is formed from a fibre composite semi-finished product, and threereinforcing profiled elements 12, which are also formed from fibrecomposite semi-finished products.

In the embodiment shown, the fuselage shell 10 is formed from apre-impregnated CFRP material (“prepreg”). The fuselage shell 10 has asurface area of several square meters. This surface is curved in a moreor less complicated manner. In the schematic sectional view of FIG. 1,for example, a transverse curvature of the fuselage shell 10 can clearlybe seen. In the embodiment shown, the reinforcing profiled elements 12are provided in the form of fibre composite parts, which are alreadyfully cured and which are laid extending on the upper surface in FIG. 1of the fuselage shell 10 in the longitudinal direction thereof. In thiscontext, the reinforcing profiled elements 12 form what are known as“stringers” (longitudinal reinforcing profiled elements) on the finishedvehicle fuselage component, on the inside of the fuselage shell. Ingeneral, the reinforcing profiled elements which are bonded according tothe invention could also alternatively or additionally form “formers”.

In the embodiment shown, the reinforcing profiled elements 12 are whatare known as “omega profiled elements”. As can be seen from FIG. 1, thecross-section of these profiled elements has two mutually spaced footportions, which each come into contact with the surface of the fuselageshell 10 and which are interconnected via an arc-shaped cross-sectionalregion which extends at a distance from the fuselage shell surface. Thearc-like cross-sectional region is composed, as shown, of two obliqueportions, which are bonded directly to the foot portions and extendobliquely upwards in a straight line, and a central portion, whichextends parallel to the foot portions (and interconnects the upper endsof the two oblique portions).

An epoxy resin system which is contained in the fuselage shell 10(prepreg), and thus the fuselage shell 10, are cured in a thermal curingprocess, explained in greater detail below, the foot portions of thereinforcing profiled element 12 which are lying on the initially still“wet” fuselage shell face, and thus this reinforcing profiled part 12,being bonded to the fuselage 10 (“co-bonding” or “co-curing” process).

Optionally, so as to improve this bonding, an adhesive film of liquid orviscous epoxy resin or the like may also be previously applied, forexample ironed on, to the foot portions of the reinforcing profiledelement 12 or to the surface of the fuselage shell 10 (at least in theregion of the foot portions).

So as to provide a particularly good connection between the fuselageshell 10 and the reinforcing profiled elements 12, the bonding iscarried out with evacuation of a space which encloses the fuselage shell10 and the reinforcing profiled elements 12 and which is delimited onthe upper face in FIG. 1 by an air-impermeable film 14. On the lowerside, this space is delimited by a mould face 16 of a moulding tool or amould 18. The space is evacuated via a ventilation line 22 to a vacuumpump (not shown). The edge of the air-impermeable film 14 is sealedagainst the mould 18 circumferentially by means of a seal 20 which isarranged on the edge of the mould face 16. As a result of theevacuation, the reinforcing profiled elements 12 are advantageouslypressed against the fuselage shell 10, and this fuselage shell 10 is inturn pressed against the mould face 16, during the curing process, insuch a way that a particularly integral connection is achieved betweenthe reinforcing profiled elements 12 and the fuselage shell 10, as wellas a high dimensional accuracy for the fuselage shell 10.

In the shown embodiment, the pressing of the parts 10, 12 is alsofurther assisted or increased in that before the start of the (thermal)curing process the previously disclosed arrangement is brought into anautoclave (pressure chamber) 24, in the interior 26 of which a pressuregreater than the atmospheric pressure, for example of approximately 5 to10 bar, is set during the curing process. The pressure is set via apressure line 28, which opens into the interior 26 of the autoclave 24,during the curing process.

However, before the actual curing, in this case by heating the interior26, is started, a tightness test is preferably carried out with regardto the sealing of the space under the vacuum film 14 (by the seal 20 andthe sealing rings 44) and the sealing of the hose interior (by theinsertion connections).

In the embodiment shown, supporting profiled elements 30 of atrapezium-shaped cross-section are used during the curing process tosupport the reinforcing profiled elements 12, and are each arranged inone of the intermediate spaces between the reinforcing profiled elements12 and the fuselage shell 10, as shown in FIG. 1. Without supportingprofiled elements of this type, the reinforcing profiled elements 12would collapse, or at least be deformed, as a result of the highpressure in the autoclave 24.

Once the curing process is complete, the arrangement of the (now cured)parts is removed from the autoclave 24 again and the supporting profiledelements 30 are removed from this arrangement again, in this case forexample drawn from the intermediate spaces in the longitudinal directionof the fuselage 10. This can be simplified, for example, in that thehose interiors are evacuated in advance via the air inlet openings, soas to reduce the transverse extent thereof or the removal resistancethereof. In this context, it should be noted that depending on thespecific application the hoses have to be drawn out from the curedconstruction over a distance of more than 10 m. If it is not necessaryto evacuate the hose interiors so as to draw the hoses out in thismanner, for example because the hoses are sufficiently flexible, it isconceivable initially to pull the optionally distally arranged endpieces from the respective ends of the profiled hose, instead ofevacuating the hose interiors, in such a way that when the profiledhoses are subsequently drawn out, these end pieces do not have to bedrawn through the cured construction.

The construction and the function of the supporting profiled elements 30are described in greater detail in the following with reference to FIGS.2 and 3.

FIG. 2 shows part of the arrangement of FIG. 1 from above, but theautoclave 24 and the film 14 are omitted in FIG. 2 for a clearerillustration of the supporting profiled elements 30.

Each of the supporting profiled elements 30 consists of anair-impermeable profiled hose 32 (of a trapezium-shaped cross-section)and end pieces 34 which are detachably inserted at the two ends of theprofiled hose and sealed against the profiled hose 32 by means of thisinsertion connection. In the partial drawing of FIG. 2, only one of theend pieces 34 can be seen for each of the profiled hoses 32.

FIG. 3 shows the region denoted as III in FIG. 2, at the end of aprofiled hose 32, in greater detail. In the shown embodiment, theprofiled hose 32 is in the form of an extruded elastomer hose (forexample a silicone hose) of the aforementioned trapezium-shapedcross-section profile, it being advantageously possible to provide theprofiled hose 32 for example as a portion which is cut off at a suitablelength from a hose supply. The end piece 34 is manufactured for exampleas a milled aluminium part (alternatively for example a plasticsmaterial moulded part) and has an outer portion 36, which projects outof the end of the profiled hose, and an inner portion 38 (in dashedlines in FIG. 3), which projects into the end of the profiled hose.Further, an optionally provided air passage opening 40, via which it ispossible to apply pressure to the hose interior during the curingprocess, is also shown in dashed lines in FIG. 3.

If the curing process takes place at ambient pressure (1 bar) ratherthan in an autoclave, the supporting profiled elements 30 at both endscould each be closed by a closed end piece 34 (without the opening 40).In particular if the curing is instead carried out at an increasedambient pressure (in an autoclave), it is recommended applying pressureto the respective hose interior at a pressure which at least correspondsto the pressure prevailing in the pressure chamber 26. For this purpose,an end piece 34 having an opening 40 of this type, which provides thispressure application, is preferably provided for each profiled hose 32at (at least) one end. In a preferred embodiment of each supportingprofiled element 30, it has an end piece 34 with an opening 40 at oneend and an end piece 34 without an opening 40 of this type at the otherend. By contrast with the shown embodiment, hose ends which are closedby means of “closed” end pieces (without an opening 40) in this examplecould also be closed in a different manner, for example by adhesion,welding or the like.

In the following, an embodiment of an “open end piece” 34 a is describedwith reference to FIGS. 4 to 6, and an embodiment of a “closed endpiece” 34 b is described with reference to FIGS. 7 to 9. These endpieces 34 a, 34 b may for example be used as the “end piece 34” of thearrangement described above (FIGS. 1 to 3).

FIGS. 4 to 6 show an end piece 34 a having an outer portion 36 a and aninner portion 38 a. The inner portion 38 a (projecting into the end ofthe profiled hose during use) has a reduced (tapered) cross-section bycomparison with the outer portion 36 a, in such a way that when theprofiled hose 32 is attached, the profile thereof is extended by theouter portion 36 in a flush manner. This has the advantage that the film14, which covers the supporting profiled element during the curingprocess, also lies fully against the ends of each supporting profiledelement 30. For this purpose, the inner portion 38 a is attached to theouter portion 36 a via a gradation 42 a which reduces the cross-section,the gradation 42 a being formed with dimensions corresponding to thethickness of the profiled hose which is attached to the end piece 34 a.The wall thickness of the profiled hose may for example be approximatelya few mm.

Again with a view to the film 14 lying fully in contact, the outerportion 36 a has an oblique face, in particular also at the left-handend thereof in FIG. 4, at which the aforementioned air passage opening40 a is also formed.

In the shown embodiment, the inner portion 38 a is provided with twosealing rings 44 a, which are spaced as seen in the longitudinaldirection of the end piece 34 a and which seal the end piece 34 aagainst the inner casing wall of the attached profiled hose 32 duringuse.

Each of these sealing rings 44 a, which are formed from an elastomericmaterial, is of an approximately rectangular cross-section and is laidin a circumferential groove which is suitably dimensioned in the regionof the inner portion 38 a. In the shown embodiment, these grooves arerectangular in cross-section, having a depth of approximately 1 mm, thecross-sectional height of each of the sealing rings 44 a beingdimensioned slightly larger than the groove depth in each case, in sucha way that about 1/10 mm of the sealing rings 44 a projects out of theassociated groove.

Aside from this profiling of the inner portion 38 a, which forms thegrooves for the sealing rings 44 a, a further gradation 46 a is providedas profiling in the shown embodiment (as seen in the longitudinaldirection), and tapers the cross-section of the inner portion 38 afurther towards the hose interior. A projection 48 a, which extendsaround circumferentially on the circumference, is formed in the regionof the hose-side end of this further tapered portion.

The projection 48 a is dimensioned in such a way that it advantageouslybrings about mechanical fixing of the attached end of the profiled hose,and thus prevents the inserted end piece 34 a from unintentionallyslipping out of the relevant profiled hose end during handling of thesupporting profiled element. A circumferential projection of this type,which is formed from the material (in this case for example aluminium)of the relevant end piece, is preferably arranged (as shown) in thedirect vicinity of the hose-side end of the inner portion 38 a.

In the shown embodiment, the air passage opening 40 a is in the form ofa threaded hole for screwing in a sleeve-like air passage screw 50 a, soas to provide the aforementioned application of pressure to the hoseinterior during the curing process. For this purpose, a shaft portion,provided with an outer thread, of the screw 50 a engages through a holein the air-impermeable film 14 (not shown in FIGS. 4 to 6). Screwing thescrew 50 a tight causes the film regions surrounding this film hole tobe clamped between a widened head of the screw 50 a and the obliqueface, visible at the left-hand end in FIG. 4, and sealed against thisoblique face. The screw 50 a is preferably formed with a bordering onthe screw head, so as to be simple to actuate, and provided with asuitable sealing disc 52 a (for example made of elastomeric material),so as to improve the sealing effect. For the passage of air (or pressureequalisation), the screw 50 a is provided with a central drill-hole 54a, which extends in the longitudinal direction of the screw.

FIGS. 7 to 9 show an embodiment of an end piece 34 b which substantiallycorresponds, in terms of construction and function, to the end piece 34a disclosed above. Only the air passage opening 40 a (along with theassociated air passage screw 50 a) which is provided in the end piece 34a is not provided in the “closed variant” of the end piece 34 b.

In FIGS. 7 to 9, functionally equivalent parts are marked with the samereference numerals (as in FIGS. 4 to 6), but with the lower case letter“b” added in each case to distinguish them from the variant according toFIGS. 4 to 6.

During use, the end piece 34 b (with the profiled hose 32 attached)forms an air-tight end of the supporting profiled element 30(ventilation of the relevant supporting profiled element 30 can beprovided as discussed via an “open end piece” (34 a) which is insertedat the other end of the profiled hose).

In the method illustrated in FIG. 1 for producing a reinforced aircraftfuselage component, the fuselage shell 10, which is formed from a fibrecomposite semi-finished product, is initially laid on the mould face 16of the mould 18. Optionally, an adhesive film is subsequently applied tothe upper surface of the fuselage 10 in FIG. 1 and/or to the footportions of the prefabricated reinforcing profiled element 12.Subsequently, the prefabricated reinforcing profiled element 12 is laidon along with the respectively associated supporting profiled elements30 and finally the air-impermeable film 14.

Before or after the space which is covered by the film 14 is evacuated,the moulding tool 18 is brought into the autoclave 24 together with theparts which are laid on. Subsequently, the pressure chamber 26 of theautoclave 24 is placed under pressure. The entire arrangement ispreferably tested for tightness, in advance or after this application ofpressure. If the result of this tightness test is satisfactory, thepressure chamber 26 is heated by means of a heating means (not shown).The parts of the component are thus cured and connected, preferably inaccordance with a predetermined progression of temperature and pressureover time.

Subsequently, the mould 18 is removed from the autoclave 24 along withthe now complete fuselage shell component (cured and rigidlyinterconnected parts 10, 12), and the film 14 is removed.

After the supporting profiled elements 30 (which have been ventilatedagain and optionally evacuated) have been removed, at least the endpieces 34 thereof can advantageously be reused (after being cleaned asnecessary), so as to provide new supporting profiled elements formanufacturing further fuselage shell components.

Advantageously, a profiled hose can initially be provided for thispurpose by cutting off a portion of a predetermined length from avirtually endless supply of an air-impermeable profiled hose, so assubsequently to insert previously used end pieces again, detachably, atboth ends of the provided profiled hose.

The supply of profiled hose may advantageously be supplied wound up on adrum for example, the length of the profiled hose which is wound upthereon (for example more than 100 m, in particular more than 200 m)making it possible to cut off a plurality of profiled hose portions,each of the currently required lengths. The supporting profiled elementsare thus provided to some extent by way of a construction kit system, itadvantageously being possible to select the length of the individualsupporting profiled elements individually and as desired by tailoringthe hose supply accordingly.

The invention therefore makes it significantly simpler to providesupporting profiled elements which are suitable for the production offibre composite components, and this in turn greatly reduces theproduction costs of the relevant fibre composite components.

In particular, the following advantages can be achieved with theinvention and the embodiments described above:

-   -   Good, simple sealing is made possible by comparison with a        casing such as vacuum film which is used during the production        of the component.    -   By using reusable end pieces, it is advantageously possible to        work with a virtually endless hose material (hose supply) during        mass production of reinforced fibre composite fuselage        components.    -   The length of a supporting profiled element which is to be        provided can advantageously be adapted in a simple manner to the        length of the relevant reinforcing profiled element. Each        reinforcing profiled element can end at any desired point on the        relevant “substrate” (for example fuselage shell).    -   Supporting profiled elements are provided according to the        invention by way of a simple, modular insertion principle, in        which at least the (relatively expensive) end pieces are        reusable.    -   It is advantageously possible to seal the profiled hose        interiors without an additional sealing measure (such as        adhesion). In particular, by using an autoclave for the curing        process, a sufficiently good sealing effect in the insertion        connection can still be ensured.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive. Itwill be understood that changes and modifications may be made by thoseof ordinary skill within the scope of the following claims. Inparticular, the present invention covers further embodiments with anycombination of features from different embodiments described above andbelow.

The terms used in the claims should be construed to have the broadestreasonable interpretation consistent with the foregoing description. Forexample, the use of the article “a” or “the” in introducing an elementshould not be interpreted as being exclusive of a plurality of elements.Likewise, the recitation of “or” should be interpreted as beinginclusive, such that the recitation of “A or B” is not exclusive of “Aand B.” Further, the recitation of “at least one of A, B and C” shouldbe interpreted as one or more of a group of elements consisting of A, Band C, and should not be interpreted as requiring at least one of eachof the listed elements A, B and C, regardless of whether A, B and C arerelated as categories or otherwise.

The invention claimed is:
 1. A supporting profiled element configured tosupport a reinforcing profiled element that is formed from a fibercomposite semi-finished product during a curing process of a method forproducing a vehicle fuselage component, in which the reinforcingprofiled element is bonded to a surface of a fuselage shell that isformed from a fiber composite semi-finished product, the supportingprofiled element comprising: an air-impermeable profiled hose having twoends; and a first end piece that is detachably inserted at a first ofthe two ends of the profiled hose so as to form an insertion connection,the first end piece being sealed against the profiled hose by theinsertion connection, the first end piece comprising an air passageopening and an air passage screw with a widened head configured to clampan air-impermeable film that surrounds the air passage opening betweenthe widened head and an outer portion of the first end piece, the airpassage opening being disposed in an oblique face of the first end pieceso that the air-impermeable film can be sealed against the oblique face,the air passage opening comprising a threaded hole configured to receivethe air passage screw, the air passage screw having a shaft portion,provided with an outer thread, configured to engage through a hole inthe air-impermeable film, the air passage screw comprising a sealingdisc configured to face the oblique face upon insertion of the airpassage screw into the threaded hole of the air passage opening, the airpassage screw comprising a central drill-hole that extends in alongitudinal direction of the air passage screw; wherein an innerportion of the first end piece projects into the first end of theprofiled hose, the inner portion comprising a first region and a secondregion, a cross-section of the second region being comparatively smallerthan a cross-section of the first region, the first region including atleast one sealing ring for sealing against the attached first end of theprofiled hose, and the second region including at least one projectionwhich extends circumferentially around the second region and is formedof the same material as the first end piece, wherein the outer portionof the first end piece projects out of the first end of the profiledhose and extends a profile of the hose in a flush manner, and wherein agradation attaches the inner portion to the outer portion, the gradationbeing formed with dimensions that correspond to a thickness of theprofiled hose.
 2. The supporting profiled element according to claim 1,further comprising a second end piece that is detachably inserted at asecond end of the profiled hose so as to form another insertionconnection, the second end piece being sealed against the profiled hoseby the other insertion connection.
 3. The supporting profiled elementaccording to claim 1, wherein the outer portion of the first end piecehas at least a second oblique face, and wherein the oblique facesfacilitate laying the air-impermeable film which is used in the curingprocess.
 4. The supporting profiled element according to claim 1,wherein the air passage opening is configured for applying apredetermined pressure to an interior of the hose during the curingprocess.
 5. The supporting profiled element according to claim 1,wherein the at least one sealing ring is laid in a circumferentialgroove which is formed on the first region of the first end piece.